diff --git a/.changeset/gentle-trains-attack.md b/.changeset/gentle-trains-attack.md
new file mode 100644
index 00000000..af5ded71
--- /dev/null
+++ b/.changeset/gentle-trains-attack.md
@@ -0,0 +1,7 @@
+---
+'preact-render-to-string': major
+---
+
+Remove trailing space for void_elements, this could fail some test_assertions as
+`<img />` will become `<img/>`, the other `VOID_ELEMENTS` this will be applied for
+can be found [here](https://github.com/preactjs/preact-render-to-string/blob/remove-trailing-space/src/index.js#L368-L385)
diff --git a/src/index.js b/src/index.js
index db6b6df1..64f00711 100644
--- a/src/index.js
+++ b/src/index.js
@@ -358,7 +358,7 @@ function _renderToString(vnode, context, isSvgMode, selectValue, parent) {
 
 	// Emit self-closing tag for empty void elements:
 	if (!html && SELF_CLOSING.has(type)) {
-		return s + ' />';
+		return s + '/>';
 	}
 
 	return s + '>' + html + '</' + type + '>';
diff --git a/test/render.test.js b/test/render.test.js
index 17391c3a..a3b8b1e2 100644
--- a/test/render.test.js
+++ b/test/render.test.js
@@ -116,7 +116,7 @@ describe('render', () => {
 
 		it('should serialize defaultChecked prop to the checked attribute', () => {
 			let rendered = render(<input type="checkbox" defaultChecked />),
-				expected = `<input type="checkbox" checked />`;
+				expected = `<input type="checkbox" checked/>`;
 
 			expect(rendered).to.equal(expected);
 		});
@@ -240,7 +240,7 @@ describe('render', () => {
 						<wbr />
 					</div>
 				),
-				expected = `<div><input type="text" /><wbr /></div>`;
+				expected = `<div><input type="text"/><wbr/></div>`;
 
 			expect(rendered).to.equal(expected);
 		});